SMACNA - Fibrous Glass Duct Construction Standards 7th & 8th Ed. Questions & Answers PDF

SMACNA - Fibrous Glass Duct Construction Standards, 7th and 8th Ed. Questions and Answers 1. The maximum temperature inside fibrous glass duct with continuous operation is __________°F. A. 250 B. 200 C. 225 D. 275...

SMACNA - Fibrous Glass Duct Construction Standards, 7th and 8th Ed. Questions and Answers 1. The maximum temperature inside fibrous glass duct with continuous operation is __________°F. A. 250 B. 200 C. 225 D. 275 2. When staple flaps are not present to hold seams and joints in position prior to application of the closure system __________ should be used. A. Hot seal tape B. Pressure seal tape C. Overlapping tabs D. Crosstabs 3. All sheet metal screws penetrating duct board shall be __________. A. 7/8 inches longer than the board thickness B. 0.5 inch (12.7 mm) longer than the board thickness C. 1 inch longer than the board thickness D. No less than 1.25 inches long 4. When staple flaps are not present, cross tabs are to be equally spaced on each side of the joint and made from __________ inch minimum lengths of closure tape. A. 4 B. 6 C. 8 D. 10 5. The maximum hanger spacing for duct 48 inches or greater is __________ feet. A. 4 B. 5 C. 6 D. 7 6. For fibrous duct board, 22 gage, 2" x 1.5" hangers may substitute for 3 inches duct hangers with widths not over __________ inches. A. 24 B. 36 C. 48 D. 52 7. All heat seal tapes shall be a minimum width of __________ inch(es). A. 1 B. 2 C. 4 D. 3 8. A __________ closure system is not suitable for use with rigid fibrous glass duct systems and does not comply with UL 181 or UL 181A. A. Pressure-sensitive aluminum foil tapes B. Mastic-pressured glycol tape C. Heat activated aluminum foil/scrim tapes. D. Mastic and glass fabric tape system (GFM) 9. For seams and joints without staple flaps you should use __________. A. Cross tabs made from 8-inch lengths of closure tape and space them equally on each side of the joint and on 12-inch centers with at least one cross tab per ductside B. Cross tabs made from 8-inch minimum lengths of closure tape and space them equally on each side of the joint and on 12-inch centers with at least one cross tab per duct side C. Cross tabs made from 10-inch lengths of closure tape and space them equally on each side of the joint and on 12-inch centers with at least one cross tab per duct side D. Cross tabs made from 8-inch lengths of closure tape and space them equally on each side of the joint and on 6-inch centers with at least one cross tab per duct side 10. Z-framing around the opening of a flange on opening requires __________ screws 6 inches on center. A. #8 x 1.25 inch galvanized B. #10 x 1. 25 inch galvanized C. #6 x 1.25 inch sheet metal D. #10 x 1.25 inch sheet metal 11. The fibrous glass duct is 36 inches by 64 inches. The maximum allowable spacing for the straight duct is __________ feet. A. 4 B. 6 C. 8 D. 10 12. The water gage is 1 inch. The contractor is installing Type 475 Board. The inside duct dimension is 22. The tie rod reinforcement is __________ inches. A. 24 B. 16 C. 48 D. Not required 13. The fibrous glass duct is 44 inches by 56 inches. The maximum allowable spacing for the straight duct is __________ feet. A. 4 B. 6 C. 8 D. 10 14. When staple flaps are not used to join seams and joints, cross tabs must be equally spaced on each side of the joint and on __________ inch maximum centers. A. 2 B. 6 C. 10 D. 12 15. A piece of fibrous glass duct is straight with a three-inch-wide channel. It is 36 inches high and 60 inches wide inside. The maximum allowable hanger spacing for this ductwork is __________ feet. A. 10 B. 8 C. 6 D. 4 16. A 45-degree fibrous glass duct elbow requires a minimum of __________ pieces. A. 1 B. 2 C. 3 D. 4 17. Cross tabs used to hold seams and joints in place prior to the application of a closure system must be made from lengths of closure tape at least __________ inches long. A. 10 B. 8 C. 6 D. 4 18. When staple flaps are not used to join seams and joints, there must be at least __________ cross tab per duct side. A. 1 B. 2 C. 3 D. 4 19. A 90-degree fibrous glass duct elbow requires a minimum of __________ pieces. A. 1 B. 2 C. 3 D. 4 20. The access door width interferes with reinforcement. The installer should install the tie rods __________ inches from each side of the door opening. A. 4 B. 6 C. 8 D. 12 21. When staple flaps are not used __________ should be used. A. Cross tabs B. Adhesive C. Snap ties D. Gum 22. All pressure sensitive tape shall be a minimum width of __________ inches. A. 2 B. 2.5 C. 3 D. 6 23. The minimum overhang for a seam without staple flaps when using pressure sensitive tape is __________ inch(es). A. 2.5 B. 2 C. 1.25 D. 1 24. Closure tape should be centered over edge of stapling flap __________ inch(es) minimum overlap. A. 1 B. 2 C. 4 D. 8 25. The contractor is installing a flanged or slip-in electric heater in the duct. The heater is 12 inches wide and is being installed in a fibrous glass duct 12 inches by 18 inches. The contractor will need __________. A. 10 square feet of 20 gage sheet metal B. 12 square feet of 22 gage sheet metal C. 9 square feet of 18 gage sheet metal D. 10 square feet of 22 gage sheet metal 26. A fibrous glass duct 24 inches by 24 inches using 3-inch-wide channel requires hanger spacing at no more than __________ feet maximum. A. 4 B. 6 C. 8 D. 12 27. Volume dampers in fibrous glass duct require __________. A. Metal sleeves B. 20 gage galvanized steel to prevent cutting into the duct board C. Mounting brackets attached with number 10 screws every 8 inches on all four sides D. Damper operator mounting flange minimum 8 inches wide 28. UL181 A requires listed enclosures be any of the following except __________. A. Pressure sensitive aluminum foil tapes B. Heat activated aluminum scrim tapes C. Mastic and glass metal tape systems D. Heat activated aluminum foil tapes 29. Pressure sensitive tape shall be a minimum width of __________ inches. A. 2 B. 2.5 C. 3 D. 4 30. Sheet metal sleeves used inside ductboard for heater applications shall extend __________ inches beyond each side of the heater. A. 12 B. 6 C. 4 D. 18 31. All screws penetrating ductboard shall be no more than __________ inches longer than the ductboard. A. 2 B. 1 C..5 D..25 32. Fibrous glass duct board may be used for __________. A. Supply air ductwork subject to 2-inch WG static pressure B. Return air ductwork only C. Low pressure fume exhaust systems D. Kitchen range hood ducts 33. The length of duct board (1-inch thick) required to fabricate a duct 40 inches wide x 16 inches high is __________ feet. Assume a flap width of 1-3/8 inches is included. (Field knowledge question) A. 4 B. 6 C. 8 D. 10 34. A 44" x 40" fibrous glass duct operating at ½-inch WG static pressure may be reinforced with a 22 gage __________. A. 1" x 1" tee B. 1" x 1" channel C. 1.25" x 1.25" tee D. 1" x 3" channel 35. The collar of a 20" by 12" diffuser connection shall be supported by a bearing plate inside the duct approximately __________ inches wide. A. 1 B. 2 C. 3 D. 4 36. A duct constructed of 1-inch thick fibrous glass duct board that is 60 inches wide shall be supported by hangers a maximum of __________ feet on center. A. 1 B. 2 C. 4 D. 6 37. 20" x 12"' diffuser connections in fibrous glass ductwork are to be supported by a bearing plate of __________ gage sheet metal. A. 18 B. 20 C. 22 D. 24 38. A 30" x 30" fibrous glass duct shall be supported by hangers a maximum of __________ feet on center. A. 1 B. 2 C. 4 D. 6 39. It is recommended that fibrous glass duct systems (when used in air conditioning systems) not exceed __________ inches W.G. A. 1 B. 1.5 C. 2 D. 2.5 40. A 48" x 48" duct constructed of 1-inch thick duct board shall be supported by hangers a maximum of __________ feet on center. A. 2 B. 4 C. 6 D. 8 41. The minimum size hanger wire for fibrous glass duct is __________ gage. A. 10 B. 12 C. 16 D. 18 42. Fibrous glass duct may be used for __________. A. Conveying air at 40°F to 250°F B. Kitchen exhaust air at 1,500 fpm C. Underground supply air ductwork D. A chemical hood exhaust duct ****Please see Answer Key on the following page**** 12/14/21  SMACNA - Fibrous Glass Duct Construction Standards, 7th and 8th Ed. Answers Answer Page # 1. A 2.1 2. D 3.3 3. B 3.1 4. C 3.3 5. A 6.2 6. C 6.3 7. D 3.1 8. B 3.3 9. B 3.3 10. D 4.9 11. A 6.1 12. D 5.2 13. A 6.1 14. D 3.4 15. D 6.1 16. B 4.3 17. B 3.4 18. A 3.4 19. C 4.3 20. A 5.17 21. A 3.3 22. B 3.1 23. C 3.1 (#16), Figure 3-1B Tape Closure Joint, Without Staple Flap 24. A 3.4, Figure 3-1 Closures  Answer Page # 25. D 6.7 Figure 6-6 indicates 22 gage sheet metal which eliminates A and C. The figure also shows the sleeve or support should extend a minimum of 6 inches past each end of the 12 inches heater. That makes the dimension of the width of the sheet metal 24 inches. The inside perimeter of the duct is 12 + 18 + 12 + 18 or 60", which would be the length of the sheet metal. 24 x 60 = 1440 square inches 1440 ÷ 144 = 10 square feet 26. B 6.1 27. A 6.8 28. C 3.3 29. B 3.1 30. B 6.7 31. C 3.1 32. A 2.1(b), 2.1(m) 33. D Field knowledge (2x width + 2x height) + add on (40” x 2) + (16” x 2) = 112” 112” + staple flap (8” approx.) = 120” 120” = 10’ 34. D 5.6, Table 5-2 Channel System Reinforcement Schedule 35. C 4.12, Figure 4-12 Register and Grille Attachment 36. C 6.2, Table 6-1 Maximum Hanger Spacing by Duct Size ID 37. D 4.12, Figure 4-12 Register and Grille Attachment 38. D 6.2, Table -6-1 Maximum Hanger Spacing by Duct Size ID 39. C 2.1(b) 40. B 6.2, Table 6-1 Maximum Hanger Spacing by Duct Size ID 41. B 6.2, Figure 6-1 Allowable Hanger Spacing, Straight Duct, 3 IN. Wide Channel 42. A 2.1(h)